Overview of the Valmont Power Station
Located at 1800 North 63rd Street, in unincorporated Boulder County, the Valmont Power Station burned coal in electricity production in the mid-1920s. In 2017, Xcel Energy concluded coal-burning operations at the site. Xcel Energy continues to operate three natural gas turbines and two solar arrays at the site to produce and distribute power throughout eastern Colorado.
During the Valmont Power Station’s coal-burning operational lifespan, coal ash was historically disposed of in a series of onsite landfills on the north end of the property near the Valmont Butte. While modern landfills must have a protective barrier installed below the coal ash, this landfill was constructed before those best practices existed. Xcel Energy must continuously monitor the landfill and the local groundwater quality under their permit requirements with the Colorado Department of Public Health and Environment and the Environmental Protection Agency’s Coal Combustion Residuals regulations.
Xcel Energy’s ongoing groundwater monitoring at the Valmont Power Station identified localized groundwater contamination near the coal ash landfill and a few neighboring properties. Xcel is required to clean up and permanently resolve the groundwater contamination at Valmont Station. Their proposed plans for addressing the groundwater contamination are outlined below, along with an overview of Boulder County Public Health’s role in the project and information on how the public can share their voice on the cleanup effort.
About Coal Ash
Coal ash is a byproduct of the combustion of coal used to produce power at power plants. Fly ash, bottom ash, slag, and flue gas desulfurization materials are all terms that represent the different types of coal combustion residuals (CCR). Coal ash is disposed of in wet form in large ponds (surface impoundments) and in dry form in onsite or off-site landfills. Once an impoundment area has reached capacity or is to be closed for other reasons, the water is drained, and the ponds are dredged. The dredged residuals are then deposited on-site in designated landfills. Coal ash can contain heavy metals and other toxic substances that can harm health if inhaled or ingested. Boulder County Public Health is working with state and federal regulators to better understand and mitigate potential health risks at this site.
Groundwater Contamination & Corrective Measures
In 2020, Xcel’s groundwater monitoring at the Valmont Power Station detected two contaminants, lithium and selenium, present in concentrations in some monitoring wells, which were above what is considered safe groundwater protection standards. The standards are set by the Colorado Department of Health and Environment and the Environmental Protection Agency to protect public health and the health of our aquifers. This contamination is linked to the coal ash stored in the landfills on the property.
Additional testing from several privately owned wells on neighboring properties to the northeast has also found concentrations of lithium and selenium above groundwater protection standards. Lithium and selenium are naturally occurring elements in rocks, soil, and groundwater. However, lithium and selenium can be potentially harmful if large amounts are ingested or if there is long-term exposure. The groundwater contamination is not believed to impact any public water supplies currently.
Health information about Selenium and Lithium in drinking water:
- Colorado Department of Public Health & Environment Fact Sheet – Lithium in Drinking Water
- Environmental Protection Agency Fact Sheet – Selenium in Drinking Water
Xcel is developing plans with a contractor to clean up the existing groundwater contamination and permanently prevent any future contamination. The proposed remediation plan involves a combination of groundwater pumping and treatment and source removal of the coal ash landfill. Xcel intends to apply the coal ash in a beneficial reuse project, where 85% of the coal ash from the landfill will be used to produce a product sold into the local ready-mix concrete market. Coal ash partially replaces cement that would otherwise need to be manufactured from mined limestone. Boulder County Public Health recognizes the potential air quality concerns related to the excavation and processing of the coal ash. We are working to advocate for best management practices and policies to address possible impacts on air quality and reduce potential community exposure.
Xcel has been sharing information about site conditions and their proposed groundwater action plan with Boulder County Public Health, the Colorado Department of Public Health and Environment, and the Environmental Protection Agency.
Additional resources from Xcel Energy:
- Groundwater & Remedy Evaluation Presentation
- Information on Lithium and Selenium
- Valmont Station Project Frequently Asked Questions
Regulation and Boulder County Public Health’s Role
The proposed site remediation activities at the Valmont Power Plant are subject to various state and federal regulations. The Colorado Department of Public Health and Environment and the United States Environmental Protection Agency are the principal regulatory bodies responsible for ensuring compliance with all regulations. Boulder County Public Health is working closely with these regulatory partners and Xcel Energy to assure compliance with all local, state, and federal requirements and best management practices. Boulder County Public Health is committed to ensuring the community’s safety through this process and engaging with the community around the Valmont Power Station to listen, share information, and answer questions.
For information on how to share your voice with Boulder County Public Health and our regulatory partners, please see the ‘Community Engagement’ information below:
It is essential to Boulder County Public Health (BCPH) and the Office of Sustainability, Climate Action, and Resiliency (OSCAR) to address the closure of the Valmont Power Plant at the grassroots community level, as it is a large-scale environmental, socio-economic, and equity concern. Collaboration between the local government and frontline community partners is crucial to tackle this issue effectively. Engaging in collaborative efforts with county staff and exchanging ideas and reflections across neighborhoods can create inclusive community-led solutions that lead to equitable outcomes.
The county is ready to support the community with resources, procedural equity, planning, and implementation processes. In the spirit of collaboration, we invite our community leaders to co-create and co-lead these community engagement efforts. To learn more about this process and to get involved, please reach out to our staff:
- Marianne Shiple – Climate Justice Program Coordinator (BCPH)
- Marina La Grave – Climate Equity Specialist at the Office of Sustainability, Climate Action, and Resiliency (OSCAR)
- Engagement Cafecito hosted by the Climate Justice Collaborative and Naropa University was held 3:30-5:30 p.m. on Nov. 16, 2023 at Naropa University Nalanda Campus (6287 Arapahoe Ave, Boulder, CO 80301).
- Engagement Meeting on Feb. 27, 2024 from 6-8 p.m. at the Boulder County Recycling Center (1901 63rd St., Boulder, CO 80301). Meeting information and an agenda will be sent to our mailing list. All are welcome!
Questions? Please email ValmontStation@bouldercounty.gov.